* Implemented cucul_draw_cp437_box().

cucul/box.c

@@ -99,17 +99,69 @@ int cucul_draw_thin_box(cucul_canvas_t *cv, int x1, int y1, int x2, int y2)
             cucul_putchar(cv, x2, y, '|');
 
     /* Draw corners */
-    if(x1 >= 0 && y1 >= 0)
-        cucul_putchar(cv, x1, y1, ',');
+    cucul_putchar(cv, x1, y1, ',');
+    cucul_putchar(cv, x1, y2, '`');
+    cucul_putchar(cv, x2, y1, '.');
+    cucul_putchar(cv, x2, y2, '\'');
 
-    if(x1 >= 0 && y2 <= ymax)
-        cucul_putchar(cv, x1, y2, '`');
+    return 0;
+}
+
+/** \brief Draw a box on the canvas using CP437 characters.
+ *
+ *  This function never fails.
+ *
+ *  \param cv The handle to the libcucul canvas.
+ *  \param x1 X coordinate of the upper-left corner of the box.
+ *  \param y1 Y coordinate of the upper-left corner of the box.
+ *  \param x2 X coordinate of the lower-right corner of the box.
+ *  \param y2 Y coordinate of the lower-right corner of the box.
+ *  \return This function always returns 0.
+ */
+int cucul_draw_cp437_box(cucul_canvas_t *cv, int x1, int y1, int x2, int y2)
+{
+    int x, y, xmax, ymax;
+
+    if(x1 > x2)
+    {
+        int tmp = x1;
+        x1 = x2; x2 = tmp;
+    }
+
+    if(y1 > y2)
+    {
+        int tmp = y1;
+        y1 = y2; y2 = tmp;
+    }
+
+    xmax = cv->width - 1;
+    ymax = cv->height - 1;
 
-    if(x2 <= xmax && y1 >= 0)
-        cucul_putchar(cv, x2, y1, '.');
+    if(x2 < 0 || y2 < 0 || x1 > xmax || y1 > ymax)
+        return 0;
 
-    if(x2 <= xmax && y2 <= ymax)
-        cucul_putchar(cv, x2, y2, '\'');
+    /* Draw edges */
+    if(y1 >= 0)
+        for(x = x1 < 0 ? 1 : x1 + 1; x < x2 && x < xmax; x++)
+            cucul_putchar(cv, x, y1, 0x2500); /* ─ */
+
+    if(y2 <= ymax)
+        for(x = x1 < 0 ? 1 : x1 + 1; x < x2 && x < xmax; x++)
+            cucul_putchar(cv, x, y2, 0x2500); /* ─ */
+
+    if(x1 >= 0)
+        for(y = y1 < 0 ? 1 : y1 + 1; y < y2 && y < ymax; y++)
+            cucul_putchar(cv, x1, y, 0x2502); /* │ */
+
+    if(x2 <= xmax)
+        for(y = y1 < 0 ? 1 : y1 + 1; y < y2 && y < ymax; y++)
+            cucul_putchar(cv, x2, y, 0x2502); /* │ */
+
+    /* Draw corners */
+    cucul_putchar(cv, x1, y1, 0x250c); /* ┌ */
+    cucul_putchar(cv, x1, y2, 0x2514); /* └ */
+    cucul_putchar(cv, x2, y1, 0x2510); /* ┐ */
+    cucul_putchar(cv, x2, y2, 0x2518); /* ┘ */
 
     return 0;
 }

cucul/cucul.h

@@ -146,6 +146,7 @@ int cucul_fill_ellipse(cucul_canvas_t *, int, int, int, int, char const *);
 
 int cucul_draw_box(cucul_canvas_t *, int, int, int, int, char const *);
 int cucul_draw_thin_box(cucul_canvas_t *, int, int, int, int);
+int cucul_draw_cp437_box(cucul_canvas_t *, int, int, int, int);
 int cucul_fill_box(cucul_canvas_t *, int, int, int, int, char const *);
 
 int cucul_draw_triangle(cucul_canvas_t *, int, int, int, int, int, int, char const *);